[datac]

If I am correct, you earlier stated that you are seeing accumulated error ? If you lost .005 in 50 moves...... this would almost always indicate a problem with pulse width/timing/edge settings. You could prove it by running 100 moves which should exactly double your error.

I'd re-examine your direction change driver requirements.....

[abond13]

If I am correct, you earlier stated that you are seeing accumulated error ? If you lost .005 in 50 moves...... this would almost always indicate a problem with pulse width/timing/edge settings. You could prove it by running 100 moves which should exactly double your error.

I'd re-examine your direction change driver requirements.....

Thanks for the reply. i will run some more tests. how dos one go about re-examining my "direction change driver requirements" also, "pulse,width,timing,edge, settings" sorry noob here.
in my mind after no change with bearing adjustments, i had thoughts of bad parallel port pins or something electronic or settings. cause i can watch the cutting move more and more positive of
center with every cut.This would explain why the first job i was running was not working out. It was a rectangular plate with holes down the center of it "a jig", i set up to mill the ends to length and also put a .125 rad.on the outside corners and the bottom (negative y side) left corner, always cut more material than the top positive. Also the hole locations on the Y was always out in the same direction.
Then i run a 90deg chamfer tool around the top edge of the hole thing, there you could really see it. its like someone shifted the Y offset positive with every pass of the tool, thanks for your help
off i go to mess with it.

[datac]

Thanks for the reply. i will run some more tests. how dos one go about re-examining my "direction change driver requirements" also, "pulse,width,timing,edge, settings" sorry noob here.

motor drivers often have very small windows of time to accomplish things. one of those important things happens to be DIRECTION timing. a definite, repeatable loss... the kind you have indicated could show that during direction change timing, the driver MISSES one or more step pulses each time direction is changed. you need to find out exactly what timing requirements are for the motor drivers you are using, then make sure your control software reflects those exact settings.

If by chance your X and Y settings are identical, and also correct, I would swap your X and Y motor drivers, then re-test your 50 moves. if the driver has an issue, your step loss should have moved to the other axis because the drive moved.

if you have repeatable and reliable step loss... like .005" in 50 moves and subsequently, .010" in 100 moves, you MUST solve this first before worrying about any hardware issues because your problems will never go away.... only get more confusing. what you really need to base your findings on though is number of DIRECTION CHANGES...... that is the moment that usually creates repeatable lost steps.

[abond13]

motor drivers often have very small windows of time to accomplish things. one of those important things happens to be DIRECTION timing. a definite, repeatable loss... the kind you have indicated could show that during direction change timing, the driver MISSES one or more step pulses each time direction is changed. you need to find out exactly what timing requirements are for the motor drivers you are using, then make sure your control software reflects those exact settings.

If by chance your X and Y settings are identical, and also correct, I would swap your X and Y motor drivers, then re-test your 50 moves. if the driver has an issue, your step loss should have moved to the other axis because the drive moved.

if you have repeatable and reliable step loss... like .005" in 50 moves and subsequently, .010" in 100 moves, you MUST solve this first before worrying about any hardware issues because your problems will never go away.... only get more confusing. what you really need to base your findings on though is number of DIRECTION CHANGES...... that is the moment that usually creates repeatable lost steps.

Thanks, i am using KL-8060 drivers
how would i find the timing requierment and adjust the direction change timing?
this might be what i need at the bottom of this link to the drivers i have there is a download that talks about DIR and PUL is that the info im needing to find? KL8060 Bipolar Stepper Motor Driver 24-80VDC 6A | Automation Technology Inc
but first i need to switch the drivers and see if the problem shifts to the other axis. or is the info about the dir and pul, what i need to go into the software and see if its set correctly?
thanks again ps could i just switch the motor cables and run the x as y and y as x just for this test? just wondering

[abond13]

aright good news, i switched drivers (motor cables) and the error stayed with the y axis driver. but, now im not sure how to fix it. thanks all for the help.

Ive went thru all settings in mach3 looking for "something" just to see if i could figure it out. i did toggle the
y axis "step low active" off just to see what it would do since the other 2 axis's did not have that selected. all it did was, allow the y axis to move in only one direction,so that dident work. I did turn "step low" on in the X axis to see what it would do, and it did not have an effect on it,it still would go in both directions.? i dont know.im just taking stabs in the dark.trying to get this thing going. wondering if its a bad driver now? i could order one and swap it out.

[datac]

aright good news, i switched drivers (motor cables) and the error stayed with the y axis driver. but, now im not sure how to fix it. thanks all for the help.

Ive went thru all settings in mach3 looking for "something" just to see if i could figure it out. i did toggle the
y axis "step low active" off just to see what it would do since the other 2 axis's did not have that selected. all it did was, allow the y axis to move in only one direction,so that dident work. I did turn "step low" on in the X axis to see what it would do, and it did not have an effect on it,it still would go in both directions.? i dont know.im just taking stabs in the dark.trying to get this thing going. wondering if its a bad driver now? i could order one and swap it out.

Find one of the Mach forums, then find someone in there using your same drives. ASK them what driver timing settings work the best, set yours accordingly. If you still end up with one driver that fails to conform no matter what axis you run with it, you could have a bad driver. Note too though, you should actually change out the driver or swap input lines to make sure it is not a problem with the pc's parallel port......

Of course you again must understand that this is based on the claim that your step loss is ALWAYS repeatable and directly recognizable by the number of direction changes called out in the toolpath. If you have erratic loss for other issues like binding and such, none of my comments really apply.

[abond13]

Find one of the Mach forums, then find someone in there using your same drives. ASK them what driver timing settings work the best, set yours accordingly. If you still end up with one driver that fails to conform no matter what axis you run with it, you could have a bad driver. Note too though, you should actually change out the driver or swap input lines to make sure it is not a problem with the pc's parallel port......

Of course you again must understand that this is based on the claim that your step loss is ALWAYS repeatable and directly recognizable by the number of direction changes called out in the toolpath. If you have erratic loss for other issues like binding and such, none of my comments really apply.

ok i posted over in the mach forum. i was wondering about the parallel port also. thanks alot, i appreciate the help, i will get back with findings. sorry for all the dumb questions but what input lines do you mean? also where do i adjust driver timing setting if i have to? thanks

[datac]

ok i posted over in the mach forum. i was wondering about the parallel port also. thanks alot, i appreciate the help, i will get back with findings. sorry for all the dumb questions but what input lines do you mean? also where do i adjust driver timing setting if i have to? thanks

Say you are using pins 1 and 2 for your troublesome axis' step/dir connections and pins 3 and 4 on an axis that works.....

You should then swap pin 1 for 3 and 2 for 4. That would tell you if you have a port issue.

I forgot where and or what Mach allows you to change for driver settings.... a good quality control can have MANY setting adjustments in order to function with the widest array of drivers.... I dont use Mach.